Excellent web frameworks
Editor: Thats what Dabo does. Its not YAWF (yet another web framework). There are plenty of excellent web frameworks out there, so if thats what you are looking for, Dabo isnt for you. But there are almost no desktop application frameworks out there, and if you want to Create applications that run on Windows, OS X or Linux, Dabo is for you!

Background
3-Tier Design
Database
Business Objects
User Interface
Multi-Platform
Community
Screenshots
License
Dabo is a 3-tier, cross-platform application development framework, written in Python atop the wxPython GUI toolkit. And while Dabo is designed to create database-centric apps, that is not a requirement. Lots of people are using Dabo for the GUI tools to create apps that have no need to Connect to a database at all.

Currently, Dabo supports MySQL, PostgreSQL, Firebird, Microsoft SQL Server and SQLite backends, but in the near future it will support all databases that have drivers that conform to the Python dbapi. These databases include:

MySQL (already supported)
PostgreSQL(already supported)
Firebird (already supported)
MS-SQL and MSDE (already supported)
SQLite (already supported)
Oracle
DB2
Sybase
Berkeley DB
Business Rules
This tier is where all the business Logic resides. You simply subclass dBizobj, set a few properties, and override a few methods. The dBizobj communicates with the database tier and the user interface tier, and enforces your business rules to your specifications. you can free download Dabo 0.9.2 now.